Compact architecture for near-to-eye display system

• US 9,285,591 B1
• Filed: 08/29/2014
• Issued: 03/15/2016
• Est. Priority Date: 08/29/2014
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Google Inc. (Alphabet Inc.)
• Inventors: Gupta, Anurag, Luttmann, Amber M.
• Primary Examiner(s): Ben, Loha
• Application Number:
  US14/473,578
• Publication Number:
  US 20160062120A1
• Time in Patent Office: 564 Days
• Field of Search: 359629-631, 359/633, 359/634, 359/636, 345 7- 9, 345/633, 348/56, 348/58, 348/148
• US Class Current: 1/1
• CPC Class Codes: G02B 2027/011 comprising device for correcting geometrical aberrations, distortion
• CPC Class Codes: G02B 2027/0123 comprising devices increasing the field of view
• CPC Class Codes: G02B 2027/0178 Eyeglass type eyeglass details G02C
• CPC Class Codes: G02B 2027/0187 slaved to motion of at least a part of the body of the user, e.g. head, eye
• CPC Class Codes: G02B 27/0093 with means for monitoring data relating to the user, e.g. head-tracking, eye-tracking
• CPC Class Codes: G02B 27/01 Head-up displays
• CPC Class Codes: G02B 27/0101 characterised by optical features G02B27/0172 takes precedence
• CPC Class Codes: G02B 27/017 Head mounted
• CPC Class Codes: G02B 27/0172 characterised by optical features
• CPC Class Codes: G02B 27/0176 characterised by mechanical features
• CPC Class Codes: H04N 13/279 the virtual viewpoint locations being selected by the viewers or determined by tracking

Abstract

An eyepiece body of an eyepiece includes an input lens positioned to couple display light into the eyepiece body along a forward propagation path, a concave end reflector disposed at an opposite end of the eyepiece body from the input lens to reflect the display light back along a reverse propagation path, and a viewing region including a partially reflective surface that redirects at least a portion of the display light traveling along the reverse propagation path out of an eye-ward side of the eyepiece body along an emission path. The partially reflective surface is obliquely angled relative to the eye-ward side and the concave end reflector is titled relative to a top or bottom surface of the eyepiece body to collectively cause the emission path of the display light to be oblique to a normal vector of the eye-ward side in two orthogonal dimensions.

Claims

1. An eyepiece, comprising:

an eyepiece body, including;

an input lens positioned to couple display light into the eyepiece body along a forward propagation path;

a concave end reflector disposed at an opposite end of the eyepiece body from the input lens to reflect the display light back along a reverse propagation path within the eyepiece body; and

a viewing region disposed between the input lens and the concave end reflector and including a partially reflective surface, the partially reflective surface to redirect at least a portion of the display light traveling along the reverse propagation path out of an eye-ward side of the eyepiece body along an emission path,

wherein the partially reflective surface is obliquely angled relative to the eye-ward side and the concave end reflector is titled relative to a top or bottom surface of the eyepiece body to collectively cause the emission path of the display light to be oblique to a first normal vector of the eye-ward side in two orthogonal dimensions,

wherein the input lens is tilted such that a second normal vector from a center point of the input lens is obliquely angled relative to the top or bottom surface of the eyepiece body.

2. The eyepiece of claim 1,

wherein the partially reflective surface is obliquely angled with an offset from 45 degrees relative to the eye-ward side to cause the emission path to have a first oblique angle in a horizontal dimension relative to the first normal vector of the eye-ward side,

wherein the concave end reflector is tilted such that a third normal vector from a center point of the concave end reflector is obliquely angled relative to the top or bottom surface of the eyepiece body to cause the emission path to have a second oblique angle in a vertical dimension relative to the first normal vector of the eye-ward side,

wherein the vertical dimension and the horizontal dimension comprise the two orthogonal dimensions.

3. The eyepiece of claim 2, wherein the first oblique angle is 6 degrees±

1 degree, the offset from 45 degrees of the partially reflective surface is 2 degrees±

1 degree, the second oblique angle is 6.7 degrees±

1 degree, the second normal vector from the center point of the input lens is obliquely angled relative to the top or bottom surface of the eyepiece body by 1.4 degrees±

1 degree, and the third normal vector from the center point of the concave end reflector is obliquely angled relative to the top or bottom surface of the eyepiece body by 2.1 degrees±

1 degree.

4. The eyepiece of claim 1, wherein the top and bottom surfaces are flat and planar.

5. The eyepiece of claim 4, wherein the eye-ward side of the eyepiece body is flat and planar and substantially perpendicular to the top and bottom surfaces.

6. The eyepiece of claim 5, wherein the eyepiece body is configured to be coupled to a head mounted display that holds the eyepiece body substantially level above an eye of a user and angles an end of the eyepiece body proximate to the input lens towards a temple region of the user such that the user looks straight forward and up to align the eye with the emission path of the display light.

7. The eyepiece of claim 1, further comprising:

a display panel for generating display light,

wherein the second normal vector from the center point of the input lens obliquely intersects the display panel in at least one dimension.

8. The eyepiece of claim 1, wherein the eyepiece body has a first cross-section size and the input lens has a second cross-section size smaller than the first cross-section size.

9. The eyepiece of claim 8, wherein a step interface between the first cross-section size and the second cross-section size is coated with an opaque material.

10. The eyepiece of claim 1, further comprising:

a gap between the partially reflective surface and the eye-ward side of the eyepiece body such that the partially reflective surface does not extend to the eye-ward side of the eyepiece body.

11. A head wearable display for providing display light to an eye of a user, the head wearable display, comprising:

a display panel for generating display light;

an eyepiece body, including;

an input lens positioned to couple the display light into the eyepiece body along a forward propagation path;

a concave end reflector disposed at an opposite end of the eyepiece body from the input lens to reflect the display light back along a reverse propagation path within the eyepiece body; and

a viewing region disposed between the input lens and the concave end reflector and including a partially reflective surface, the partially reflective surface to redirect at least a portion of the display light traveling along the reverse propagation path out of an eye-ward side of the eyepiece body along an emission path; and

a frame assembly to support the eyepiece body and the display panel for wearing on a head of the user with the viewing region positioned above the eye of the user,

wherein the partially reflective surface is obliquely angled relative to the eye-ward side and the concave end reflector is titled relative to a top or bottom surface of the eyepiece body to collectively cause the emission path of the display light to be oblique to a first normal vector of the eye-ward side in two orthogonal dimensions.

12. The head wearable display of claim 11, wherein the input lens is tilted such that a second normal vector from a center point of the input lens is obliquely angled relative to the top or bottom surface of the eyepiece body.

13. The head wearable display of claim 12,

wherein the partially reflective surface is obliquely angled with an offset from 45 degrees relative to the eye-ward side to cause the emission path to have a first oblique angle in a horizontal dimension relative to the first normal vector of the eye-ward side,

wherein the concave end reflector is tilted such that a third normal vector from a center point of the concave end reflector is obliquely angled relative to the top or bottom surface of the eyepiece body to cause the emission path to have a second oblique angle in a vertical dimension relative to the first normal vector of the eye-ward side,

wherein the vertical dimension and the horizontal dimension comprise the two orthogonal dimensions.

14. The head wearable display of claim 12, the second normal vector from the center point of the input lens obliquely intersects the display panel in at least one dimension.

15. The head wearable display of claim 11, wherein the top and bottom surfaces are flat and planar.

16. The head wearable display of claim 15, wherein the eye-ward side of the eyepiece is flat and planar and substantially perpendicular to the top and bottom surfaces.

17. The head wearable display of claim 16, wherein the frame holds the eyepiece body substantially level above the eye of the user and angles an end of the eyepiece body proximate to the display panel towards a temple region of the user such that the user looks straight forward and up to align the eye with the emission path of the display light.

18. The head wearable display of claim 11, wherein the eyepiece body has a first cross-section size and the input lens has a second cross-section size smaller than the first cross-section size.

19. The head wearable display of claim 18, wherein a step interface between the first cross-section size and the second cross-section size is coated with an opaque material.

20. The head wearable display of claim 11, further comprising:

a gap between the partially reflective surface and the eye-ward side of the eyepiece body such that the partially reflective surface does not extend to the eye-ward side of the eyepiece body.